


Wield the Knife

by cenotaphy



Category: Supernatural
Genre: Angelic Grace (Supernatural), Angst, Angst with a Happy Ending, Blood and Violence, Body Horror, Castiel is Loved (Supernatural), Dark, Dean Being Alastair's Star Pupil, Dean Winchester Has Self-Worth Issues, Hugs, Hurt Castiel (Supernatural), Hurt/Comfort, Implied/Referenced Torture, M/M, Major Character Injury, POV Dean Winchester, Pre-Slash, Protective Dean Winchester, Protective Sam Winchester, Sam Winchester keeping his head in a crisis, Team Free Will (Supernatural), Torture, Torturer Dean Winchester, can be interpreted different ways depending on how you squint, hand-holding, mostly these boys just love each other a lot okay
Language: English
Status: Completed
Published: 2020-03-29
Updated: 2020-03-29
Packaged: 2021-02-28 18:27:11
Rating: Not Rated
Warnings: Graphic Depictions Of Violence
Chapters: 1
Words: 4,474
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/23371654
Author URL: https://archiveofourown.org/users/cenotaphy/pseuds/cenotaphy
Summary: "Where's the angel?" Dean demands to the room at large.He's prepared to level his shotgun at someone to get an answer, but he doesn't need to. A vampire, needle teeth extending reflexively as it scents the blood on Dean's forehead, lifts a shaky hand to jab at a spot in the center of the floor."Down," it whispers. "There."***(Or: Castiel has been missing for weeks, and when the Winchesters finally find him, they'll have to act fast to save him.)
Relationships: Castiel & Dean Winchester, Castiel & Dean Winchester & Sam Winchester, Castiel & Sam Winchester, Castiel/Dean Winchester, Dean Winchester & Sam Winchester
Comments: 43
Kudos: 423





	Wield the Knife

**Author's Note:**

> Anyone who's seen the film Annihilation can probably guess the scene that inspired this. *covers eyes*

It turns out Dr. McGinnis, fucking psychopath that he was, had been indulging his taste for experimentation by keeping a whole sideshow of freaks chained up in his basement. But none of them, Dean can see in the harsh fluorescent lighting, are the particular weirdo he's looking for.

"Where's the angel?" Dean demands to the room at large.

He's prepared to level his shotgun at someone to get an answer, but he doesn't need to. A vampire, needle teeth extending reflexively as it scents the blood on Dean's forehead, lifts a shaky hand to jab at a spot in the center of the floor.

"Down," it whispers. "There."

"There's a trapdoor," whispers the girl next to him, barely into her teens judging by her tiny frame.

Dean stamps over to the center of the room and pulls back an oilcloth rug that is, indeed, covering a small trapdoor. He hauls it open and sees wooden steps, leading down into darkness.

"Creepy," he mutters, and starts down the steps.

The light from the basement only stretches halfway down the steps, so Dean fumbles his phone out and turns the flashlight on one-handed. The space he's descending into is small, an oubliette of sorts, the featureless walls melting into their own gloom, and there's a pale shape near the bottom of the stairs.

Dean freezes mid-step. "Cas," he calls, low, his heart in his throat. There's no response.

He takes two more steps and his foot lands on what feels like stone. Water sloshes against the edge of his boot; there's a film of it covering the cell floor. He raises his phone higher and there's no mistake. It's Cas, undressed, curled on his side in the inch-deep water with his back to the stairs.

"Cas," Dean says again, his voice suddenly hoarse with the weight of all those weeks spent searching.

He has the sense to put his gun on the stairs, out of the water, and then he's rushing forward. He drops to his knees beside Cas— _Christ_ , the water is freezing cold—and turns him onto his back. The angel's eyes are closed, his face gaunt and colorless. Dean pans the light down and breathes a sigh of relief as he sees a faint but discernible rise and fall to Cas's chest.

"Hang on pal," he mutters. He reaches for Cas's limp hand, the fingers of which are about the same temperature as the water around them. "We're gonna get you out of—"

Under the bone-pale skin of Cas's abdomen, where his ribcage gives way to the curve of his sunken belly, something moves.

Dean jerks back in shock. It was a trick of the light. It was a tremor in his hand. It has to be.

But when he shines his phone carefully at Cas's torso, there it is again, something large shifting under Cas's skin, distending his stomach as it goes.

"Fuck," he bites out, recoiling. Then,

"SAM!" he yells over his shoulder. "Down here, under the trapdoor!"

"SAM!" he calls again when there's no answer, and hears the clatter of Sam's feet on the wooden stairs.

"I'm coming, Dean, I'm here, is Cas— _Jesus Christ_."

"Yeah," Dean grits out. Under his hand, Cas stirs and makes a feeble noise; Dean whips his light up to frantically scan his friend's face, but Cas's eyes are still closed. He spasms once, splashing more water against Dean's jeans, and then goes still.

"We have to get him out of here," says Dean.

*

The kitsune girl who'd helped them kill McGinnis is waiting in the basement when they struggle back through the trap door, Cas a dead weight between them. She covers her mouth with one hand as Cas comes fully into view.

"He'll be fine," Dean snarls, because he won't entertain the thought of the alternative.

"No, it's just." She swallows, moves aside so that he can reach the stairs to the main floor. "When the screaming stopped, we all thought he had died."

*

Cas starts to cry out as they rush him up the stairs into the kitchen, his body jerking in their grip. The skin below his ribs ripples and heaves until Dean half-expects it to split open. He averts his gaze so that he can focus on not tripping. McGinnis's corpse lies in the corner where the last shotgun round had dropped him; his blood is spattered over the bars of the kitsune girl's cage. They lift Cas onto the narrow kitchen table and stand, panting, beside it.

"Dean..." Sam's eyes are huge. He looks helplessly at Dean. "What do we do."

Dean stares down at whatever is undulating under the skin of his best friend's torso and swallows back the bile rising up in his own throat. "We have to get it out," he says hoarsely.

" _How_?"

Dean unbuckles his belt with trembling fingers that he wills to be still. He passes it under the tabletop and buckles it closed over Cas's legs, just above the knees.

"Take yours off too," he grunts to Sam. "Round his chest. Hurry."

As if to punctuate his words, Cas arches on the table and groans, a desperate sound. Sam struggles with his belt for a moment, finally wrapping it tightly around Cas's chest, binding him to the table.

Dean wipes his sweaty hands on his jeans.

"Give me the blade," he says.

Sam blanches, even as he pulls the angel blade out. "Dean—we can take him back to the Bunker, we can find out what this is—"

"There's no time. We have to cut it out," says Dean. Some instinct, some surety deep inside him, is telling him that they can't leave this thing in Cas one moment longer than necessary. "He'll heal, Sam."

"If we don't _kill_ him," says Sam again, desperately. "Dean, if we—if we cut too deep, or if we hit something—"

 _That's why it has to be me_ , Dean thinks. His throat closes up, and it's not from the sight of Cas's straining body. He takes the angel blade from Sam's hand and it's remarkable, really, how it all comes rushing back. How his grip adjusts ever so slightly on the haft as the blade stops being a weapon and starts being a tool.

"Hold him still," he tells Sam.

"You sure you know what you're doing?" Sam asks quietly. Because Sam still doesn't _get_ it.

Dean almost laughs at that. Because he could just shrug and say that he hopes he does. He could just say that they don't have a choice. But the fact is that Dean trained under Alastair. Dean spent a decade learning how to do this and he knows _exactly_ what he's doing.

The penny takes a moment longer to drop for Sam, and then Dean sees remorse flit across his brother's face as the realization hits him. But Sam says nothing else, just backs up to the end of the table where Cas is turning his head agitatedly from side to side. He splays his huge hands over Cas's shoulders and nods once, grim.

Dean swallows one more time, his throat bone-dry, the angel blade icy in his hand. Then he starts to cut.

Cas begins to scream almost immediately, eyes rolling wildly beneath their lids. His body thrashes against the belts and Sam grunts as he has to lean all his weight onto Cas's shoulders to keep the angel from jack-knifing up against the restraints. Dean keeps his eyes fixed determinedly downward, and keeps going.

Silvery-white grace glimmers weakly around the blade, but after the first few incisions there's mostly just blood. It gushes from the wound, through his fingers and over Cas's twitching body onto the table, and Dean ignores it, works through it. He doesn't think about what he's doing to the body of his best friend; he doesn't think about what must be going through Sam's head, watching this. He cuts through the layers of tissue and peels them back one by one, the skin, the yellow fat, the red muscle, until—until—

It looks like an eel. Like a monstrous eel folded up in Cas's belly, bulging out of it now that Dean's opened up the abdominal cavity, writhing and sliding over and along itself with no head or tail visible. He hears Sam retch, feels pretty close to vomiting himself. The only thing keeping the bile down is the knowledge that if he did he'd pretty much be puking directly into Cas's guts. Actually, the coils of the thing are concealing any internal organs, or _maybe it's eaten them_ , Dean thinks in sudden horror, _fuck_.

"Dean," Sam chokes out, and Dean looks up and meets his brother's enormous eyes. Cas has gone mercifully limp, his screams dwindled now to a shapeless, unceasing whimper. "Dean, get it out, god, take it out of him."

Dean sets the blade down on the edge of the table, because his other hand needs to stay free to—god, to hold back the flap of muscle and skin he's peeled away from Cas's torso. The pale monster slithers and twists in Cas, moving endlessly, _how many feet long is the fucking thing_ , Dean thinks. He reaches out for one of the coils, praying it isn't coated in fucking acid or something, and wraps right hand around it.

It's cool to the touch despite the fact that it's presumably been living amid the steamy heat of someone's internal organs. His hand barely fits around it; he can feel it twisting under his grip, undulations growing more agitated. The low sounds Cas has been making stutter for an instant, like the sound is catching in the angel's throat, and then suddenly rocket up the scale into an ear-piercing howl.

Dean swallows hard, trying to block out the sound. He steels himself and slowly, carefully, he starts to pull. The thing in his hand wriggles as he gradually reels it out, wincing at the knowledge of what it must be doing to Cas. He has to fight the desire to haul it out hand over hand, get it out of his friend as fast as possible—god knows what the thing could be wrapped around, in there. Sam isn't looking anymore; his head is bent, his mouth by Cas's ear, lips moving, whatever he's whispering inaudible over the sounds of Cas's frantic agony.

Dean unspools the thing for what feels like an eternity but can't actually be more than a minute, and one end finally comes free, the tail lashing in mid-air, one end still buried in Cas's insides somewhere—and then the whole process stops with a jerk, because the other end _doesn't come free_. Dean tugs a little harder, both hands wrapped around the monstrosity as it thrashes, and meets resistance, as if it's anchored somehow, deeper where he can't see.

"Please!" Cas screams suddenly, the word cracking midway through. Dean looks up just in time to see Cas's eyes fly open, pointed sightlessly at the ceiling. " _Please_ ," Cas mouths again, and there's no sound to it, like his throat has closed around the word. Sam makes a choked, stricken noise.

Dean swallows hard. He keeps one hand locked tightly around the eel's midsection, and he thinks, _forgive me_ , and he reaches the other hand into Cas. He follows the serpentine body by touch, reaching deeper, feeling things shift around his hand and trying not to think about how much more damage he's doing to this body, this vessel that anchors Cas to the material plane—

" _Dean_!" Dean looks up again and this time he's skewered by Cas's gaze, suddenly focused—Cas's eyes are wide, glassy, the pupils blown to huge black suns. The tendon's in Cas's throat are taut as he strains his neck up from the table to lock eyes with Dean. " _Dean_ —kill me, _just kill me_ — _Dean, please_ —"

"Cas, hang on," says Sam urgently. Dean can't speak. His hand is—god help him, his hand is _wrist-deep_ inside Cas. Sam cups the back of Cas's head with one enormous palm. "It's okay, we've got you, hang on, we've got you."

Cas doesn't seem to hear; he drops his head against Sam's palm and screams again, long and keening and wrecked. Under Dean's fingertips, he feels something different—subtle ridges, indentations where there had been smooth slickness before. He squeezes, crushing it in his hand until he feels something _give_ under his fingers and the resistance slackens and Cas gives one final jerk and goes still, but Dean can't think about that now, as—finally, _finally_ , he pulls the whole goddamn thing the hell _out_ of Cas.

It has to be at least six feet long, and the head—there's _no_ head, it just ends in gill flanges, a ridge of what might be bone, and then a circular jaw like a lamprey's. The concentric rings of teeth are dark red, dripping. The thing flails in his hands, the rasping fangs swinging dangerously close to Dean's wrist as he backs away from the table, away from Cas.

"Dean—here." Sam, thank _fuck_ , Sam is there and he has a large metal trash can. Dean all but throws the lamprey-thing in and it contorts violently in the bottom of the bin, its body slapping against the sides.

"Get your lighter," Sam barks, emptying a bottle of something viscous and golden—cooking oil?—over the thing. Thank god Sam is keeping his head, because Dean's incapable of doing more than following basic orders right now—he keeps staring at the eel, at its gnashing rotary of teeth, teeth that were _in_ Cas. It's all he can do to fish for his lighter with shaking fingers. His hands, so steady on the knife, are trembling now; it takes him three tries to finally click the flame to life.

The eel, or lamprey, or whatever it is, this godforsaken thing McGinnis found or made or magicked to embed in Cas like a parasite, goes up in flames in the trash can. It doesn't smell like burning anything _normal_. It smells...chemical, like ammonia, like rot. Dean watches just long enough to see the skin blackening and crisping as the body jerks in its death throes, and then he spins back to the table.

"Cas?" he ventures. Cas lies supine on the table, eyes closed. The wound gapes from his belly.

Sam goes to kneel by Cas's head, murmuring something in Cas's ear. Dean frantically watches Cas's chest, searching for the telltale rise and fall of breath, but there's nothing, and maybe Dean was wrong, maybe Cas didn't have enough grace, maybe Dean did too much, cut too deep.

"Sam," says Dean, helplessly. "He isn't healing."

"Come on, Cas," Sam says. He's looking intently into Cas's face, reaching with one hand for the pulse point in Cas's throat.

"Come on, buddy," Dean mutters. He clenches his fists. Greenish smoke rises from the mouth of the trash can. "Cas, please."

But Cas just lies there, unmoving, the wound in his torso yawning like a crimson void. Sam is still trying to find a pulse, his face drawn and grim, his jaw starting to clench as the seconds tick on. Dean starts to reach out and stops as he takes in his own hands, red halfway to the elbow. Cas's blood. His hands are soaked in it.

"Dean," Sam whispers, and Dean doesn't look up, doesn't lift his gaze to see whatever finality Sam's face is going to hold. He stares at his hands, and below them to Cas, and he realizes he's making, without meaning to, a raw sound of denial somewhere in the back of his throat, because this is something he's only ever seen in his nightmares, Cas's blood staining his hands scarlet, Cas dead by Dean's hand. And now it's real and it can't be, it _can't_ be, this can't be happening— _Cas_ , he thinks, his thoughts whiting out, _Cas_. He lowers his palms to grip the edge of the table instead, bows his head, feels a tremor running up his arms, down his spine. He killed Cas. He—he _killed_ — _Cas_ , he prays, for all the good it'll do him now, _Cas, I'm sorry, please, please_ —

"Dean," Sam hisses again. Dean finally looks up and freezes. A ring of people surrounds them.

It's the monsters from the basement, the ones McGinnis had been keeping imprisoned. He sees the kitsune girl among their ranks and guesses she must have freed them from their chains.

"Dammit, Sam," he growls under his breath, because it'd been Sam who reached out over McGinnis's corpse to unlock the cage door. The girl might've hated McGinnis but at the end of the day she's still a monster with no reason to leave two hunters alive. Sam and his bleeding heart are going to get everyone killed some day. _Everyone who's left_ , some part of his mind supplies numbly. Louder, he says, "You lot stay the hell back."

They don't retreat, but they don't step back, either. It's disconcerting, how they're all staring—their faces solemn, their hands at their sides. They might almost be keeping vigil. Dean doesn't like the idea of that at all, and decides that making them tomorrow's problem is worth not having them in some weird-ass circle around him.

"Door's behind me," he snaps, and hopes they don't call his bluff, because no way can he and Sam take them all at once. "Get out. All of you. You're free, so take your chance while you can."

There's a beat of silence, and then one of them—vampire or werewolf, Dean assumes, since they look otherwise ordinary—moves. Dean and Sam tense at the same time, but she only reaches for the hem of her shirt and pulls it up, showing a completely ordinary expanse of her stomach. Dean stares at her.

"Steel-toed boot," she tells him. "It ruptured something. I was bleeding internally. The angel healed me."

That _would_ be just like Cas, that _stupid_ stubborn son of a bitch, weakening himself for no fucking reason at all other than his own goddamn principles. Wouldn't be a surprise if that's how he was captured in the first place, Dean thinks, his eyes stinging suddenly; he can imagine Cas walking into a trap while trying to rescue one of these sorry bastards, _the fucking idiot_.

He swallows past the lump in his throat and opens his mouth to snap that if she's telling the truth, then Cas was a moron for wasting his grace. Not like a bust kidney would've killed her kind, so he wasn't saving her life. But another one of the prisoners is speaking now, tugging their tattered collar down to show their throat.

"Silver blade. I was bleeding out. Slowly." His eyes flash gold—a shifter. "The angel saved me."

And now more of them are stepping forward, pointing to invisible injuries.

"Stake through my chest. It punctured a lung. The angel got it out and healed me."

"McGinnis shot me in the knee. I told the angel to save his grace, but he healed me anyway."

"My wrist was shattered. The angel pulled his chain out of the wall to get to me. McGinnis beat him for it."

Dean knots his jaw, fighting back the torrent of grief that threatens to cut his knees out from under him. What is this, some kind of fucked up memorial service?

The kitsune girl steps forward. Dean stares at her, bewildered. She isn't looking at him—she's looking down at the angel on the table, her eyes unreadable. She reaches out and puts a palm on Cas's arm.

"What are you—" Dean starts, and the words die on his tongue as the girl lifts her hand away and a faint silvery glow shimmers from the spot she'd touched. It fades into Cas's skin almost immediately.

What the fucking hell.

The kitsune girl steps back, and the vampire takes her place, reaches out for a moment, leaves a patch of that same silvery radiance for a moment before Cas's body absorbs it.

"Dean," Sam whispers, "Dean, that—it looks like—"

It looks like grace. But that's impossible. It's _impossible_ , and it keeps happening, as the monsters file up to Cas, touching him lightly in the same spot.

"Dean—look." Sam clutches at his sleeve.

The wound is knitting itself together, blue-white light flaring at its edges, hiding the damage, flaring up brightly enough that Dean has to avert his eyes. The last of the monsters performs the bizarre laying on of hands and steps back, and the kitchen is so utterly silent that when Cas suddenly twitches and _inhales_ , the sound is the loudest thing in the world.

Dean feels his legs give way. He buckles against the table, holding himself up, his mind going blank with overwhelming relief as Cas's fingers spasm with sudden life, as Cas's eyes flutter open and sharpen into focus.

" _Cas_ , oh my god." Sam's fingers fly over the belt at Cas's shoulders, unfastening it, and then Sam is hauling Cas up into a sitting position, fingers digging into Cas's shoulders.

"S'm...?"

Sam drags Cas into him, his arms wrapped around the angel, his face buried in Cas's shoulder. Dean still can't speak. His throat works around nothing, he can't breathe, Cas was dead on this table and now he's alive. Cas is _alive_.

Cas lifts his eyes and looks at Dean over Sam's flannel-clad shoulder.

"Dean," he says, the word a rasp. Of course it's a rasp. Cas screamed himself hoarse while Dean cut him open on this table. Cas's blood is still pooled on the varnished pine, on the white tiles below. In the creases below Dean's nails. Dean wants to throw up.

Sam lets go of Cas and then, inexplicably, turns around to face Dean.

"Dean," Cas says again, stronger. He lifts a hand but Dean can't move, he's paralyzed. He should leave. Cas is alive, and Dean should leave, and never touch Cas with these hands again—

"Dean," Sam says, like a warning, like an order, and there's a sudden fierceness to his eyes. Sam's face is wet; a muscle jumps in his clenched jaw. "Dean, don't you dare," Sam says in a low voice that's very nearly a snarl, and he grabs Dean by the upper arm— _Christ_ , Dean's little brother is strong, always has been—and pivots on one heel, hauling Dean bodily over and shoving him at Cas. Dean stutters, torn between putting up his hands in defense and not wanting his bloody hands to come anywhere near Cas right now, or maybe ever again.

Cas reaches his arm out. His hair is still wet, wild tufts of it sticking out in every direction. There are tears pooled in his lashes.

"I'm sorry," Dean chokes out. "Cas, I—"

"Dean." Cas's voice cracks. " _Please_."

It's the breaking of Cas's voice that does it, like it's breaking Dean's self-loathing at the same time. Dean steps forward—almost stumbles, like he's being dragged in by some kind of undeniable gravity. Cas clutches the front of Dean's shirt and sort of _folds_ into him, forehead against Dean's sternum, hair tickling Dean's chin.

"I'm sorry," Dean whispers again. The words come out garbled. He's crying, he realizes. He presses his lips against the crown of Cas's head and screws his eyes shut. "I'm so sorry."

Cas doesn't say anything. He slides his hands along Dean's ribs and around to Dean's back. His fingers curl against Dean's shoulder blades, their grip tightening urgently.

Dean blinks back more tears and thinks about how Cas almost didn't wake up, how the last time Dean ever touched Cas would have been to eviscerate him. Slowly, he brings his arms up, curves one palm against the back of Cas's neck, presses the other between Cas's shoulders, against the protruding knobs of his spine— _god he's thin_ , Dean thinks, _can angels starve to death?_

Cas's breaths are hitching—just shy of being sobs, his bare chest juddering shallowly—and Dean thinks distantly that if angels can go into shock Cas is almost certainly in shock, and they should get him a blanket, or some _clothes_ at least, Jesus, and then get the hell out of this fucked up torture house, get back to the Bunker where Dean can get some goddamn soup into this fucking idiot angel—and then—

And then Cas can leave, if he wants to. Or Dean can leave, if Cas doesn't want him around, if Cas doesn't feel safe around Dean anymore, ever again—

"Dean," Cas sighs, and Dean freezes, wondering if his frantic thoughts are slipping into inadvertent prayer. "Dean, I know what you did for me."

 _What I did_ to _you_ , Dean thinks, viciously.

Cas sighs again and reaches back to remove Dean's hand from the back of his neck. Dean flinches, but Cas just pulls their joined hands down, into the empty space between their bodies. He laces his fingers through Dean's.

"Thank you," he says quietly, into Dean's chest.

Cas is alive, Dean thinks again. Cas is alive, and they found him, and Dean sure as hell doesn't deserve any thanks for what he did, but Cas is _alive_ and he, he doesn't hate Dean, and maybe it'll be okay. Maybe it will. He curls his fingers around Cas's hand.

"Hey." Sam is beside them, something large and shapeless in his hands—a blanket. He drops it in Cas's lap and carefully unbuckles the belt from Cas's legs. Dean finally tunes in to his surroundings and realizes that the kitchen is empty except for the three of them.

"Where—"

"They left," Sam says quietly. "They all left, after..." He gestures at Cas.

Dean hadn't even heard them go. Jesus, some hunter he is. John Winchester is probably turning in his metaphorical grave.

"They—left?" Cas squints around the room, holding the blanket against his now-unmarked stomach with his free hand. "The other people who were trapped here? Are they..."

"They're okay, thanks to you, you giant sap," says Dean crossly. His hand tightens around Cas's. "And _you're_ okay, thanks to them."

Cas looks between the two of them. "I am...okay." The last word lilts up, almost questioning, as if seeking reassurance.

"You're okay, Cas," Sam confirms gently. He puts a hand under Cas's elbow and nods to Dean; the two of them help Cas swing his legs over the edge and stand up from the table. Cas sways on the spot, face paling impossible further with the effort of standing. Dean leans in automatically, taking more of his weight; on Cas's other side Sam is doing the same thing, the two of them supporting the angel between them.

"Alright, pal," says Dean. "Let's go."

"Where," Cas pants, "are we...going." He hasn't let go of Dean's hand.

"Home," says Dean.

**Author's Note:**

> Thanks so much for reading; hope you enjoyed it! As always, comments are so, so very appreciated--I bottle them up for savoring on rainy days. <3


End file.
